NEW YORK -- Lexus plans to offer a seven-seat crossover, either by bringing out a new vehicle or by increasing the size of the venerable RX 350.

"Third-row seating is the No. 1 issue we hear from dealers," Lexus Division chief Jeff Bracken said at the auto show here. "We feel like we're missing a 35,000-units-a-year opportunity. We're working hard to rectify that."

Lexus' crossover mainstay is the RX 350, a mid-sized five-seater that in the best of economic times has sold more than 100,000 units a year.

The RX is based on the platform of the Toyota Highlander, which was redesigned this year. But the Lexus variant won't arrive until late 2015, to make room for the launch of the compact NX 200t and NX 300h five-seat crossovers arriving this winter.

Lexus has a seven-seat SUV -- the GX 460 -- but it is a body-on-frame SUV with a trucklike ride. There has been speculation that a car-based seven-seat crossover would reduce the need for the GX 460, but a Lexus source said the GX 460 is highly profitable for the automaker, even at low volumes.

It has been 11 years since Lexus unveiled the HPX seven-seat, car-based crossover concept at the New York auto show -- and seven years since a LF-Xh crossover concept appeared at the 2007 Tokyo Motor Show. Plans for a production version of the LF-Xh were halted with the recession.

Now, such a vehicle appears back on the agenda. Toyota has applied for a trademark for the TX nameplate. Toyota product planners are secretive about whether the TX would use the Highlander-Camry-Avalon front-wheel-drive architecture for packaging benefits, or use the Lexus IS/GS sedans' rear-wheel-drive architecture for a sportier feel.

Still, the TX coding could merely be for a seven-seat variant of the RX 350. The 2014 Highlander kept the same 109.8-inch wheelbase, but gained nearly 3 inches of overall length to 191.1 inches. Despite the length increase, the Highlander's third-row seat is cramped, which might not mesh with Lexus owners' luxury requirements.

"It could be any number of solutions," Bracken said. "We could bring it to market in 2016 or 2017. If we can get it, that's the priority. We won't be bothered if it steps on RX. We want it."